Moisture responsive switch actuator

ABSTRACT

A moisture responsive actuator is employed for controlling the operation of a fluid operated sprinkling or irrigating system or the like. The moisture responsive actuator is provided with hygroscopic material which expands in response to contact with rain water to depress a switch to deactivate the sprinkling system, the hygroscopic material contracting upon a drying thereof to release said switch whereupon the sprinkling system is activated.



1. A moisture responsive actuator which comprises: a housing, a switch located within the housing, means for electrically connecting said switch into a fluid sprinkling system, and moisture absorptive means cooperatively associated with said switch, said moisture absorptive means including at least one absorptive member capable of expanding in response to a predetermined amount of moisture in contact therewith to activate said switch so as to deenergize said sprinkling system, said absorptive member being further capable of retracting upon a drying thereof to deactivate said switch so as to energize said sprinkling system.
 2. A moisture responsive actuator, according to claim 1, wherein said moisture absorptive means includes a plurality of absorptive members in stacked relationship with said switch.
 3. A moisture responsive actuator, according to claim 2, which further includes: adjustable means for providing a predetermined amount of force on said absorptive members in contact with said switch so as to permit said switch to operate in response to a predetermined amount of moisture in contact with said absorptive members.
 4. A moisture responsive actuator, according to claim 3, wherein the absorptive members are comprised of hygroscopic material and are fungus resistant.
 5. A moisture responsive actuator, which comprises: a housing, a switch located within said housing, means for electrically connecting said switch into a fluid sprinkling system. moisture absorptive means cooperatively associated with said switch, said moisture absorptive means being of hygroscopic material and fungus resistant and including a plurality of absorptive members in stacked relationship with the switch, said absorptive means capable of Expanding in response to a predetermined amount of moisture in contact therewith to activate said switch so as to deenergize the sprinkling system, said absorptive means being further capable of retracting upon a drying thereof to deactivate the switch so as to energize said sprinkling system, adjustable means for providing a predetermined amount of force on said absorptive means in contact with the switch so as to permit said switch to operate in response to said predetermined amount of moisture in contact with said absorptive means, and said housing including an outer cup-shaped member having a plurality of circumferentially spaced openings in the sleeve thereof, an inner cup-shaped member located within said outer cup-shaped member and having a plurality of circumferentially spaced openings therein, and means for providing relative rotary movement between said housings for positioning said openings with respect to each other for adjustably controlling air currents passing to said absorptive members.
 6. A moisture responsive actuator, according to claim 5, wherein each cup-shaped member is provided with at least one opening therein for permitting moisture to freely pass therethrough.
 7. A moisture responsive actuator, according to claim 3, wherein the adjustable means includes: a shank for receiving said absorptive members, means for supporting said shank in a fixed relationship with said actuator, and resilient control means cooperatively associated with said shank for imparting a desired force upon said absorptive members and switch.
 8. A moisture responsive actuator which comprises: a housing, a switch located within said housing, means for electrically connecting said switch into a fluid sprinkling system, moisture absorptive means cooperatively associated with said switch, said moisture absorptive means including a plurality of absorptive members in stacked relationship with said switch, said absorptive means capable of expanding in response to a predetermined amount of moisture in contact therewith to activate said switch so as to deenergize said sprinkling system, said absorptive means being further capable of retracting upon a drying thereof to deactivate said switch so as to energize said sprinkling system, and adjustable means for providing a predetermined amount of force on said absorptive means in contact with said switch so as to permit said switch to operate in response to said predetermined amount of moisture in contact with said absorptive means, said adjustable means including a shank for receiving said absorptive members, means for supporting said shank in a fixed relationship with said switch, and resilient control means cooperatively associated with said shank for imparting a desired force upon said absorptive members and switch.
 9. A moisture responsive actuator, according to claim 8, wherein said switch includes a resilient member, and the lowermost absorptive member is in intimate contact with said resilient control means.
 10. A moisture responsive actuator, according to claim 9, which further includes: connecting means extending from said housing for connecting said switch to a location above the ground.
 11. A moisture responsive actuator which comprises: an outer cup-shaped housing, an inner cup-shaped housing, each of said housings being provided with a plurality of circumferentially spaced openings, means for providing relative rotary movement between said housings, a switch located within said inner housings, means for electrically connecting said switch into a fluid sprinkling system for maintaining said system normally operative, moisture absorptive means cooperatively associated with said switch, said absorptive means being comprised of a plurality of hygroscopic, disc-shaped, fungus resistant members in stacked relationship and capable of expanding in response to a predetermined amount of rainfall in contact therewith to activate the switch so as to closE said sprinkling system, said absorptive members contracting upon a drying thereof to deactivate the switch and thereby cause said sprinkling system to reopen, and adjustable means for providing a predetermined amount of force on said absorptive members so as to permit said switch to operate in response to said predetermined amount of rainfall in contact with said absorptive members. 